Is the clunking coming from the front or the rear?
Try jacking the car up from the rear and putting it on stands. Loosen the lower shock mount bolt (17mm). Then put a plank of wood on the jack and jack up each of the rear wheels to ride height to simulate the weight of the car being on that wheel/suspension. Tighten the bolt now, and then lower the wheel, and then take the car off the stands.
In simpler terms: the lower bolt should be tightened at "ride height" so you can either crawl under and do it while it's sitting on the ground, or jack it up and jack the wheel up to simulate weight/ride height.
Try jacking the car up from the rear and putting it on stands. Loosen the lower shock mount bolt (17mm). Then put a plank of wood on the jack and jack up each of the rear wheels to ride height to simulate the weight of the car being on that wheel/suspension. Tighten the bolt now, and then lower the wheel, and then take the car off the stands.
In simpler terms: the lower bolt should be tightened at "ride height" so you can either crawl under and do it while it's sitting on the ground, or jack it up and jack the wheel up to simulate weight/ride height.